Menstrual bleeding is a part of normal life for women. The onset of menstruation, termed menarche, usually occurs at the age of 12 or 13. The length of a woman's monthly cycle may be irregular during the first one to two years, and may stabilize for many years in a consistent pattern. Once the menstrual cycle stabilizes, a normal cycle may range from 20 to 40 days, with 28 days being an assumed common average. Age, weight, athletic activity and alcohol consumption are several factors that affect menstrual cycles. For example, younger women (under the age of 21) and older women (over the age of 49) tend to have longer cycle times, generally averaging 31 days and over. Similarly, women who are very thin or athletic also have longer cycles, or no cycles. In contrast, women who consume alcohol on a regular basis tend to have shorter cycle times.
Menstrual fluid is made up of blood and components other than blood, such as endometrial cells, cervical mucus and vaginal secretions. The various inconveniences to women resulting from menstrual bleeding have prompted attempts to regulate or control the outflow of menstrual bleeding. Some sort of pad has been used for centuries, and more recently, newer devices have been proposed. For example, vaginal tampons were introduced a few decades ago. Vaginal tampons are common catamenial devices made of absorbing material and are inserted into the vagina. Due to their absorbent material, tampons absorb fluid upon contact, such as menstrual fluid exiting the cervical canal, and function as reservoirs by delaying the exit of the menstrual fluid from the body.
Tampons present several problems in their use. One problem is that tampons cannot prevent leakage of menstrual fluid all of the time. For example, menstrual fluid may not be absorbed by the tampon because the tampon is saturated, or because the tampon does not provide an adequate seal with the vaginal walls.
Efforts to prevent leakage with tampons have included additional fluid reservoirs added to the tampons, increased absorbency of the absorbent materials found in tampons, use of intravaginal balloons to provide for a better seal, and use of absorbing pads to capture the fluid escaped from the tampon. Super absorbent materials created unforeseen consequences due to prolonged use of a tampon. The materials allowed for the growth of bacteria and led to Toxic Shock Syndrome in those women using a super absorbent tampon. Toxic shock Syndrome is caused by the toxins released by the bacteria Staphylococcus aureus. It is believed that not changing a tampon for a long time can cause staphylococcal bacteria to rapidly multiply, releasing toxins into the bloodstream, leading to the shock syndrome or possible death.
Another catamenial device is the menstrual cup. Generally, a menstrual cup is a cup-shaped intravaginal device for collection of menstrual fluid and is usually made of a flexible material impervious to fluid. The cup is inserted into the vaginal canal to collect menstrual fluid and prevent leakage from the vaginal orifice. It is also generally bulky, necessarily of large diameter, and may be difficult to insert and remove. It has a resilient circular rim significantly larger than the diameter of the vaginal orifice it has to pass through during insertion and during removal. Insertion and removal may be an uncomfortable and difficult task. Furthermore upon removal, it is hard to prevent spillage of the contents.
What is needed are methods and devices that allow for a collection of menstrual fluid that is provided once for each menstrual cycle and does not need to be changed frequently by the individual. Such methods and devices would be leak-proof and may even provide other beneficial purposes.